function playSound(e) {
    // console.log(e.keyCode, '////');
    let keyCode = e.keyCode
    const key = document.querySelector(`.key[data-key="${keyCode}"]`)
    const audio = document.querySelector(`audio[data-key="${keyCode}"]`)
    console.log(audio)
    if (!key) return
    key.classList.add('playing')
    audio.play()
    // setTimeout(() => {

    // }, 70 )
    // 65 -> A playing 
}
window.addEventListener('keydown', playSound)
const keys = document.querySelectorAll('.key')
//不需要i 

function removeTransition(e) {
    if (e.propertyName !== 'transform') return;
    //console.log(e.target)
    e.target.classList.remove('playing')
}
for (let key of keys) {
    key.addEventListener('transitionend', removeTransition)
}
